Phospholipid Polymer Biointerfaces for Lab-on-a-Chip Devices

Abstract

This review summarizes recent achievements and progress in the development of various functional 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer biointerfaces for lab-on-a-chip devices and applications. As phospholipid polymers, MPC polymers can form cell-membrane-like surfaces by surface chemistry and physics and thereby provide biointerfaces capable of suppressing protein adsorption and many subsequent biological responses. In order to enable application to microfluidic devices, a number of MPC polymers with diverse functions have been specially designed and synthesized by incorporating functional units such as charge and active ester for generating the microfluidic flow and conjugating biomolecules, respectively. Furthermore, these polymers were incorporated with silane or hydrophobic moiety to construct stable interfaces on various substrate materials such as glass, quartz, poly(methyl methacrylate), and poly(dimethylsiloxane), via a silane-coupling reaction or hydrophobic interactions. The basic interfacial properties of these interfaces have been characterized from multiple aspects of chemistry, physics, and biology, and the suppression of nonspecific bioadsorption and control of microfluidic flow have been successfully achieved using these biointerfaces on a chip. Further, many chip-based biomedical applications such as immunoassays and DNA separation have been accomplished by integrating these biointerfaces on a chip. Therefore, functional phospholipid polymer interfaces are promising and useful for application to lab-on-a-chip devices in biomedicine.

Biodegradable poly(ester urethane)urea elastomers with variable amino content for subsequent functionalization with phosphorylcholine

“…The water absorption for PEUU-NH 2 polymers increased after PC moiety grafting, due to the hydrophilicity of the PC moiety [33]. In relating the water absorption data to the degradation data, the results were generally as expected for incubation in buffered saline, with the most hydrophilic polymers showing significant mass loss at 16 wk.…”

Synthesis and surface properties of polyurethane end‐capped with hybrid hydrocarbon/fluorocarbon double‐chain phospholipid

“…Phospholipids consisting of hydrophilic and hydrophobic groups are one of the major components that form a bilayer structure to construct a biomembrane. The most representative natural phospholipid analogue is 2‐methacryloyloxyethyl‐phosphorylcholine (MPC), which was designed and synthesized by Ishihara10 and Nakabayashi et al Polymeric materials containing MPC units have been employed in various biomedical applications, because they can significantly reduce nonspecific protein adsorption and thrombus formation 10, 11. Distinctly, phospholipid polymers containing MPC have also been utilized to advance biocompatibility of PUs by coating, chemical grafting, and blending 3, 12, 13.…”

Physisorbed surface coatings for poly(dimethylsiloxane) and quartz microfluidic devices

“…For PDMS devices and to a lesser extent also for quartz, a number of surface modifications have been explored [20, 26]. Three main strategies for surface modifications are commonly employed.…”

“…However, due to its excellent optical properties, quartz remains a highly interesting material for LOCs. Recently, suitable surface coatings for quartz were investigated, such as the introduction of phospholipid polymers to modify EOF in a quartz microfluidic chip [26]. …”